Question:
Mark the tick against the correct answer in the following:
$\left|\begin{array}{ccc}a^{2}+2 a & 2 a+1 & 1 \\ 2 a+1 & a+2 & 1 \\ 3 & 3 & 1\end{array}\right|=?$
A. $(a-1)$
B. $(a-1)^{2}$
C. $(a-1)^{3}$
D. none of these
Solution:
$\Rightarrow(\mathrm{a}-1)^{3}$